Treatment of a malocclusion characterized by open bite with Class III pattern can be difficult to treat since such a malocclusion develops as a result of the interplay of many different etiological factors. Skeletal open bite cases are usually characterized by an increase in the vertical growth of the maxillary posterior dentoalveolar segments. The application of conventional reverse headgears and application of the mesially directed force below the center of resistance of maxillary dentition would tend to increase the anterior open bite. An intrusion of posterior teeth becomes more difficult with older age, mechanical treatment options are limited in adult patients. Orthognathic surgery is indicated in adult patients with severe open bite and Class III skeletal pattern with retrognthic maxilla. For the treatment of borderline cases, and those individuals who are reluctant to surgery, the search for a new treatment modalities continues.
Previous studies have shown both the effects and side effects of the application of protraction forces on the maxillary complex. Until today most of the appliances which were developed could not prevent the upward and forward rotation of the maxilla. The most important things to be considered in maxillary protraction are the point of the force application and the direction of the force. As the mandible is attached to the head with temporomandibular joint, it rotates around the condylar axis when opening and closing the mouth. It is impossible to stabilize the force system in reverse pull headgear, which takes anchorage from the chin, since the movement of the mandible doesn't allow us to apply a consistent force. Another very important aspect, which needs to be considered, is the uncertain effect of orthopedic forces on the TMJ and on mandibular growth. In growing children force application'to the chin by reverse-pull headgear causes downward and backward rotation of mandible.